1. Field of the Invention
The present invention, in general, relates to personal grooming devices and, more particularly, to toe and finger nail clippers.
Nail clippers, the term herein including either toe or finger nail type of clippers, are generally well known.
Nail clippers have certain problems. For example, prior art designs tend to spray the clippings into a room. The clippings may be sharp and can even spread infection. Therefore, it is desirable to contain clippings.
However, prior art nail clippers include a center post that engages with a pivoting lever. The pivoting lever, pressing upon a ridge in the center post applies pressure to the clipper sufficient to urge a pair of opposite sides, and therefore also the blades, toward one-another during use. This is described in greater detail hereinafter.
The center post, though necessary, provides an obstruction that certain of the clippings inevitably must impact. The clippings bounce off of the center post and are scattered. Any prior art type of modification intended to retain the clippings has proven to be ineffective when they are bouncing off of the center post.
Other prior art types of nail clippers do not fold sufficiently flat for storage. Others do not apply leverage that can create sufficient force to cut through difficult nails without requiring a great deal of force by the user.
Additionally, prior art nail clippers include considerable metal that has been machined. This is considerably more expensive than plastic, for example. However, all prior art designs have heretofore included an all metallic nail clipper if opposing parallel blades are used, with perhaps some plastic surround components as well. This has been expensive to manufacture.
There is a need for an inexpensive nail clipper. There is a need for a disposable nail clipper that is also inexpensive. Such a device could be given away at finer hotels or sold for minimum cost. It could also be a free item that included advertising, for example.
Nail clippers are expensive because of the machining that is required to manufacture the metal portions thereof. The top and bottom blades must not only be cut to a fine edge, but they must align precisely so as to abut one-another when closed. It is relatively inexpensive to make a blade, but the manufacture of two opposing blades that mesh precisely together and abut each other when closed is what drives up the cost of manufacture of these types of prior art nail clippers. Additionally, each blade includes a remaining portion that forms one-half of a body of the prior art nail clipper. Each prior art blade is formed from a single piece of metal that includes two bends (radiuses) and a blade that has a cutting edge. Accordingly, the cost of manufacture is substantially increased. The construction of this common prior art type of nail clipper is described in greater detail hereinafter.
Also, because nail clippers include so much metal, they are detected at airport security checks and often result in the searching of personal sundries that would not otherwise be so scrutinized. The metallic nail clipper is typically taken away from the owner during a security screening. The owner is then faced with a return to a non-secure area and shipping the nail clipper from the airport, which typically takes over two weeks to arrive or loss of their nail clipper what would otherwise be confiscated by security personnel who have been instructed to view it as a potentially dangerous weapon which, of course, is a debatable assessment. Either way the all metallic nail clipper is likely to be detected and the owner will be without a nail clipper when they arrive at their intended destination.
It is desirable that a nail clipper include very little metal so that it does not register as a potential threat during airport check-in procedures. An acceptable amount is similar to the amount of metal found in a few coins, at most. Therefore, the ideal nail clipper would not include significantly more metal than that provided by the cutting blades.
As mentioned briefly before, a very common prior art type of a nail clipper includes a pair of opposing metallic blades that include a right angle radius and a remaining portion that extends to the rear of the nail clipper where the two remaining portions are joined together. Each of the opposing blades typically includes a slight curvature to correspond better with the curvature that most people prefer for their finished nails, although the opposing blades can include a cutting edge that is straight, if desired. A chord taken across the opposite ends of the cutting edge of each opposing blade is generally perpendicular with respect to a longitudinal axis of the remainder of the nail clipper.
The opposing blades are normally disposed in a parallel and spaced-apart relationship with respect to each other. A connecting post passes through an opening provided in an upper remaining portion. The post is attached to a lower remaining portion. A lever cooperates with an upper end of the post and bears upon an upper surface of the upper remaining portion. As the lever is urged toward the upper remaining portion it applies an upward force to the post and a corresponding downward force to the upper remaining portion that, together, urge the upper remaining portion and the lower remaining portion toward each other.
As the upper and lower remaining portions are urged together the cutting edges of both opposing blades are also urged toward each other. The cutting edges of the two opposing blades are in a spaced-apart parallel relationship with respect to each other when they are maximally disposed away from each other and they remain in a spaced-apart and parallel relationship with respect to each other as they are urged closer together. When the cutting edges of both of the opposing blades are urged fully toward each other the cutting edges abut each other and are parallel with respect to each other when they are in contact with each other. Accordingly, for this common prior art type of nail clipper the cutting edges of the blades are always parallel with respect to each other.
During use a finger nail or a toe nail is disposed between the two opposed blades when the lever is in a fully raised position and the two cutting edges are disposed maximally away from each other. As the two cutting edges are urged toward each other the nail is simultaneously being severed by each of the two cutting edges. Accordingly, the nail is being cut simultaneously on both sides of the nail. An audible snap is typically heard at the moment the nail is severed when the cutting edges of the opposing blades make contact with each other.
It is important to note that this type of prior art nail clipper experiences considerable mechanical stress (i.e., force-loading) as it cuts the nail because cutting is occurring simultaneously across the entire width of the cutting blade and also because cutting is occurring simultaneously on both sides of the nail. This has heretobefore required that the blades in their entirety and interconnecting portions of the prior art nail clipper be formed of steel to withstand the magnitude of the mechanical stresses (i.e., forces) that are experienced.
It is useful to consider that prior art types of metallic nail clippers that have a cutting edge which is perpendicular to the longitudinal axis of the clipper and that cut both sides (top and bottom) of the nail simultaneously actually can be considered as having two elongated blades. Each of the blades can be seen as including a cutting edge that is provided at a forward end of each blade.
As mentioned above, the two elongated blades each include a ninety degree bend proximate the cutting edge and the remaining portion of each cutting blade extends rearward to form the body of the nail clipper. Each of the two remaining portions are joined together at a rear of the remaining portion, often by spot welding or by the use of a fastener, with the cutting edges facing toward each other and disposed in a spaced-apart and parallel orientation. The metallic lever and post, as mentioned above, is used to draw the two cutting edges together.
An inherent spring constant of each remaining portion of the two extended blades is used to supply a force to urge the blades apart. By including a slight rear angle in the remaining portions prior to where the two remaining portions contact each other and are secured together, a distance between the two remaining portions increases from the rear of the nail clipper moving forward toward the cutting edges. By controlling the magnitude of the rear angle the maximum amount of gap between the opposing cutting edges is determined.
Each blade and each remaining portion of each blade is formed of a continuous piece of metal. The post of the prior art type of nail clipper is also formed of metal. Therefore all load bearing components that experience significant loading of these common prior art types of nail clippers are formed entirely of metal. Accordingly, in general the use of metal for these component parts of these prior art types of nail clippers have been the only way to provide the strength that is required to sever the nail across its width simultaneously along both the top and bottom of the nail.
Therefore, any of the known prior art types of nail clippers that is not formed entirely of metal (for the load-bearing components) or which includes an intermediate portion that is made from plastic or from some other non-metallic material and which supports the cutting blades must use a scissor-type (also known as a shear cut) of cutting action rather than the two opposing blades, as described above, which abut each other in order to withstand the magnitude of forces that are experienced during use. A scissor cut experiences considerably less stress that does the common prior art type of opposing parallel spaced-apart blade nail clipper because the nail is only being severed at a point when a scissor or shear cut is utilized. Severing the nail at a single point requires considerably less force than does severing the nail along the entire width of the nail simultaneously on both sides of nail. Severing the nail simultaneously along its width is a cutting of the nail along a line, either along a straight or a curved line depending on the shape of the cutting blades.
As the nail is continually sheared the point where the nail is being cut moves across the width of the nail, progressing further away from a pair of shear handles that control the shear blades. Therefore, considerably less mechanical stress is experienced by the prior art type of nail clipper utilizing a scissor cut than by the prior art type of nail clipper utilizing parallel opposing blades that cut simultaneously across the entire width of the blades. Because of the lower forces experienced by a scissor cut the prior art use of plastic members that support metal blades for a nail clipper has been possible.
It is, of course, possible to include plastic members that support metal blades which may abut each other along their cutting edges for very light duty low-stress cutting applications, but it has not heretobefore been possible to do so for any device intended to cut finger or toe nails. However, there has been a long standing need to provide a nail clipper for use with finger nails and toe nails that includes a body portion formed of a plastic for the reasons mentioned throughout this disclosure.
It is also useful to note that finger and toe nails can come in various thicknesses and that considerable force can be encountered when simultaneously cutting across the width of the blade and through especially thick nails as can occur, for example, by nails that have been compromised by fungal infection. This can further increase the loading that is experienced by a nail clipper.
However, a significant first disadvantage to a shear type of cut as found with any prior art nail clipper that includes a plastic member to support a metallic cutting blade is that a shear includes a wide opening into which a user can over insert the tip of their finger or toe and risk cutting of the fleshy part of the finger tip or tip of the toe during insertion. This problem is especially acute for the visually impaired and for those with other disabilities.
Preventing cutting of the fleshy part of the finger or toe is an important consideration. While prior art types of spaced-apart opposing parallel cutting edge (blade) nail clippers provide some benefit over shear types of nail clippers it is still possible to over insert the nail and cut the fleshy part of the finger or toe. Also, the quality of cut is likely to vary from nail to nail as some nails are likely to be cut shorter while others are cut longer.
People desire a nail clipper that provides a constant depth of cut from nail to nail for optimum appearance and they want to minimize and preferably eliminate the possibility of cutting the finger. For example, people typically desire that their nails be of equal length after cutting to provide a uniform appearance. Also, people may desire that a predetermined amount of the lighter portion that is common at the tip of the nail to remain after cutting. A type of cut that provides this appearance is commonly referred to as a “French manicure”.
Accordingly, it is not possible for unskilled users of any type of prior art nail clipper to prevent the possibility of cutting the fleshy tip of the finger or toe and it is not possible to precisely control the depth of cut from nail to nail or provide a French manicure. Therefore, many people pay a manicurist to provide these services. However, this is challenging even to a skilled manicurist and especially so to a manicurist of lesser skill. Even a manicurist could benefit from the use of a nail clipper or set of nail clippers that each include means for controlling the depth of cut.
A second significant disadvantage to the use of a shear cut (of any prior art device intended for cutting finger/toe nails) is that the user must exert and maintain considerable force at all times while urging the nail in a direction that is toward the intersecting cutting edges of the shear type of nail clipper. This is necessary because as the shear blades are drawn together they create an angle of intersection between the two shear blades that applies a force (i.e., a force vector) to the nail which tends to urge the nail away from the point of intersection as the blades are drawn closer together.
In order to cut the nail with a scissor or shear type of cut the user must simultaneously close the shears while supplying a force urging the nail toward the shear blades. This effect is not noticeable when cutting a sheet of paper using paper shears. This is because the paper is easy to cut and thin. Being thin, the shear blades tend to be disposed at a less severe angle at the point of cut than they would if the paper (or object being cut) were thicker. Therefore, a greater percentage of the force applied to the paper by the shears is in a downward direction while less of the force is applied to the paper in a horizontal direction. However, a finger nail or toe nail is considerably harder and thicker than is a sheet of paper. Accordingly, the horizontal force component that is applied to the nail by the shear blades and which tends to urge the finger or toe nail away from the shear blades is considerably greater when cutting finger or toe nails than when cutting through paper with a pair of scissors.
Not only is this difficult to coordinate, but there is considerable risk that the nail could be urged away from a position of contact with the shear blades for any of several possible reasons. If the user is cutting a small amount of finger nail, for example, the small amount of nail could suddenly be severed simply by urging the nail toward the shear blades. The moment the nail is severed an acceleration of the finger will occur that can drive the fleshy part of the finger that is near the nail into the cutting edges of the shear blades. The finger can be cut, perhaps severely so. If the nail is urged away from contact with the shear blades because the user is unsteady, the same risk of cutting the finger arises. While this is difficult for users in general it is especially difficult for those with impaired vision or diminished hand-eye motor control to accomplish. For example, people in hospitals, nursing, and convalescent homes are unable to use shear type nail clippers for these reasons.
Accordingly, there is a long-standing need to provide a nail clipper with opposing parallel cutting blades that abut each other that is safe to use.
Also, there is a long-standing need to provide a nail clipper with opposing parallel cutting blades that abut each other that includes less metal.
Also, in nursing and convalescent homes for the reasons mentioned herein, shears cannot be provided for the residents to trim their own nails, less they injure themselves. However, the prior art nail clippers that include opposing parallel cutting blades that abut each other are too expensive to routinely provide to the residents. Also, it is possible to over-insert a finger into the prior art nail clippers that include opposing parallel cutting blades that abut each other when closed and to cut the fleshy part of the finger. For this reason, the residents are often prevented from cutting their own nails and must rely on assistance from staff to cut their nails.
Also, due to failing memory, the residents are apt to lose or to leave their own personal nail clippers (typically provided by family members) in community areas. The staff, upon finding such a nail clipper, is often unable to determine the correct owner and is reluctant to guess and provide a found nail clipper to the wrong person because of the risk of spreading viruses, bacteria, and fungal infections.
Accordingly, there is a need for a low cost nail clipper that includes opposing parallel cutting blades which abut each other that is low in cost. Similarly, there is a need for a nail clipper that includes opposing parallel cutting blades which abut each other that can be readily identified. For example, a plastic body could be provided in a variety of colors or designs to provide a visual means of identification. Similarly, a plastic body of a nail clipper could be written on by the use of a permanent market to identify the owner. Additionally, a plastic body could include Braille markings to identify ownership or any other desired attribute of the nail clipper.
Accordingly, there is also a long standing need to provide a means for controlling the depth of cut of a finger (or toe) nail by a nail clipper of the type that includes opposing parallel cutting blades which abut each other. Similarly, there is a need to provide a set of nail clippers that each include means for controlling the depth of cut of a finger (or toe) nail and where each clipper provides a different depth of cut. Additionally, there exists a need to provide a means for indicating the degree of depth of cut on a nail clipper that limits the depth of cut. There is a need to identify the depth of cut of a nail clipper by visual or by tactile means.
Accordingly, there exists today a need for a nail clipper with blade-insert that helps ameliorate the above-mentioned problems and other difficulties.
Clearly, such an apparatus would be a useful and desirable device.
2. Description of Prior Art
Nail clippers are, in general, known. While the structural arrangements of the above described known types of devices may, at first appearance, have similarities with the present invention, they differ in material respects. These differences, which will be described in more detail hereinafter, are essential for the effective use of the invention and which admit of the advantages that are not available with the prior devices.    U.S. Pat. No. 7,210,230 to Wurzel, that issued on May 1, 2007;    U.S. Pat. No. 7,020,964 to Han, et al., that issued on Apr. 4, 2006;    U.S. Pat. No. 6,941,657 to Choi, et al., that issued on Sep. 13, 2005;    U.S. Pat. No. 5,964,033 to Wolf, that issued on Oct. 12, 1999;    U.S. Pat. No. 5,621,974 to Rose, et al., that issued on Apr. 22, 1997;    U.S. Pat. No. 5,488,772 to Dababneh, et al., that issued on Feb. 6, 1996;    U.S. Pat. No. 5,353,505 to Okada, that issued on Oct. 11, 1994;    U.S. Pat. No. 5,331,739 to Basangy, that issued on Jul. 26, 1994;    U.S. Pat. No. 5,074,041 to Wagner, that issued on Dec. 24, 1991;    U.S. Pat. No. 4,819,673 to McMullen, Jr., that issued on Apr. 11, 1989;    U.S. Pat. No. 4,776,090 to Grassi, that issued on Oct. 11, 1988;    U.S. Pat. No. 4,130,937 to Kim, that issued on Dec. 26, 1978;    U.S. Pat. No. 3,914,866 to Applegate, that issued on Oct. 28, 1975;    U.S. Pat. No. 796,389 to Wright, that issued on Aug. 1, 1905; and    U.S. Pat. No. 327,065 to Burton, that issued on Sep. 29, 1885.